Team Fortress 2

Team Fortress 2, released by Valve in 2007 as part of The Orange Box, is one of the most influential multiplayer shooters ever made, even though it's an oddity on a retro DOS catalog. Its roots go back to a Quake mod, and Valve spent nearly a decade reinventing it, eventually landing on a stylized, cartoonish art style inspired by mid-century illustration that made it instantly recognizable and helped it age far better than its photorealistic peers.

The heart of the game is its nine distinct classes, from the nimble Scout to the tanky Heavy, the sneaky Spy and the supportive Medic, each with a clear role and personality. That asymmetry, combined with objective modes like Capture the Flag, Payload and Control Points, created endlessly varied team dynamics. Valve's writing and character shorts gave the mercenaries genuine comedic charm that extended the game's culture far beyond the matches themselves.

TF2 also pioneered the free-to-play plus cosmetic-economy model that now dominates the industry, with hats and item trading becoming a phenomenon in their own right. Years on, it's still played, still funny, and still a masterclass in readable, class-based multiplayer design. Its blend of accessibility, depth and personality is why so many later hero shooters owe it an obvious debt.